This invention relates to a station which is included in a time division multiple access (often abbreviated to TDMA) communication network, such as a TDMA satellite communication network.
A conventional TDMA communication network comprises a plurality of stations each of which is communicable with one another through an up-link and a down-link frame. The up-link and the down-link frames include a plurality of up-link time slots and a plurality of down-link time slots. For carrying out communication, each of the stations sends a transmission burst in a preassigned one of the up-link time slots. Thus, the transmission burst is transmitted to one or more of other stations which are collectively called a first one of the other stations. In addition, each of the stations can receive a reception burst in a prescribed one of the down-link time slots. The reception burst is transmitted from one or more of the other stations which are collectively called a second one of the other station.
In Japanese Prepublication (Kokai or Publication of Unexamined Patent Application) No. 10,544 of 1982 for an invention by the present applicant, a time division multiple access satellite communication network is disclosed which comprises a preselected one of a plurality of earth stations as a control station. In this prepublication, each of the earth stations has a communication time interval which is assigned by the control station. The communication time interval is decided with reference to a communication traffic which is predicted in each of the earth stations. The communication time interval can be changed by the control station in response to requirements of each earth station. In other words, the control station collectively controls the communication time intervals of the earth stations.
However, it is a problem in this network that a change of the communication time interval requires a long time, for example, at least several tens of seconds. Therefore, operation is slow in relation to the change of the communication time interval. This is because communication must be carried out between the control station and each of the other stations. In addition, it is necessary to avoid overlap of transmission bursts on one another after the communication time interval is changed.